[doc] Add debugging information to play scripts in SSH

[tbarbette]

trafficstars

While this is a bit redundant, I think it is good debugging advice to explain how to load the ipython scripts from the SSH shell. Probably, like me, most people do not really remember that a modified IPython is launching a ".py" script, after writing simple run.py for years.

Preview of generated doc:

[tbarbette]

Poke @GuillaumeDerval :)

[anthonygego]

Merged in ce6a6055d90b929683dedc38e41212675fc16832